Gas-liquid energy transmission



Marh 15, 1960 T. W. KENNEDY GAS-LIQUID ENERGY TRANSMISSION Filed April 24, 1958 INVENTOR. THOMAS W. KENNEDY ATTYS.

GAS-LIQUID ENERGY TRANSMISSION Thomas W. Kennedy, Wayne, Pa., assig nor to the United States of America as represented by the Secretary of the Navy Application April 24, 1958, Serial No. 730,733

7 v 4 Claims. (Cl. 102-16) (Granted under, Title 35, U.S. Code (1952), see. 266) The invention described herein may be manufactured and used by or for the Government of the United States of America for governmental purposes without the pay- "ment of any royalties thereon or therefor.

constructed that they cannot be exploded until they are submerged in order to prevent injury to personnel handling the mine preparatory to planting.

In the past, it was the practice to incorporate mechanical safety features in the firing mechanism of the mines so that the primer could not be initiated unless the mine was submerged. Although the safety feature of these firing mechanisms was adequate, they were not reliable weapons because upon long periods of submergence in sea water, the mechanical firing mechanisms became corroded and rusted to such an extent that the firing mechanism became inoperative.

In order to correct this defect, some mines were constructed with a ported chamber interposed between the primer and the booster charge or main explosive. The force of the blast created by initiation of the primer is insufficient to ignite the explosive when the chamber is filled with air which is a poor transmitter of shock. When the mine is submerged, and the chamber is filled with water via the ports, the force of the blast of the initiator is carried more efiiciently through the chamber to ignite the main charge. This type of firing mechanism is not entirely reliable because sparks from the initiation of the primer may 'fiy across the empty chamber detonating the main charge if the igniter is initiated accidently during handling or storage.

2,928,345 Patented Mar. 15, 1960 Referring now to the drawing which shows the apparatus in section, the detonating system indicated generally at 11 is disposed within a mine casing shown in a partially broken away section at 12. One or more ,of

' the walls 13 of the assembly have a plurality of ports 14 therein, connecting via tubes 17 in the casing an interior chamber 16 with the surrounding air or water, as the case may be. An electrically initiated primer 18 secured to a plug 19 is suitably arranged within chamber 16 and is adapted to be fired upon passage of an electrical current through the firing resistor 21. Since the fusing per se forms no part of this invention, the apparatus providing and applying the current at the proper time is shown only diagrammatically as a switch 22 and a battery 23 herein; it being well within the purview of one skilled in the art .to provide a suitable fusing arrangement. A hollowed compartment 24 is formed within an enlarged plug'24 at one end of the body. and

is fluidly connected to chamber 16 by the port 26 Slideably disposed within this compartment is a piston 27 adapted to be acted upon by the force of the explosion the drawing thereby to prevent actuation of the main explosive in the event that the mine is inadvertently jarred during handling or storage so that the primer is initiated.

When the mine is planted, sea water enters through ports 14 to fill chamber 16. .Since the water transmits shock energy more'efficiently than air, the explosion of the primer 18 drives firing pin 28 in the second chamber 33 with great speed and force to detonate the booster charge 29 which in turn initiates the main explosive 31. On the other hand, when the primer is initiated prior to submergence of the mine, the force of the explosion does not drive piston 27 to the right against the biasing force of spring 30 with sufficient force to cause initiation of the booster by firing pin 28 since the air in chamber 16 transmits shock inefficiently.

From the above description, it is apparent that a means is provided whereby the shock transmitting char- It is-an object of this invention to provide a new and improved submersible ordnance initiating system which will not detonate the main explosive charge even though the primer is ignited unless the ordnance device is submerged in water.

Another object of this invention is to provide a new and improved ported chamber ordnance initiating system whichhas few moving parts and is not rendered inoperative by corrosion of the working parts upon prolonged exposure to sea water.

In brief, the invention includes a novel firing mechanism for submersible ordnance. In this mechanism the safety feature depends upon a gap and a baflie member disposed between the primer and the booster charge while reliability depends upon a liquid shock transmitting medium, which is used to transmit the energy of the exploding primer to a plunger, which in turn is driven against the booster charge detonating it. The liquid medium or barrier is composed of water which fills the acteristics of the medium which exists between the primer and the firing pin plunger for igniting the booster charge may be altered to arm or disarm the ordnance device without incorporating complex mechanical apparatus in the system. This simple and positive arming operation utilizes the principle that different materials have different degrees of effectiveness in transmitting shock wave energies from the primer. Not only does this invention obviate the difficulties presented by complex mechanical systems, but it also provides an improved safety feature over the prior art ported chamber type of arming device since by providing the baflle member comprising plug 25 and piston 27 there is no danger that flying sparks from an accidentally initiated primer will ignite the booster before the mine is submerged.

Although the invention has been described with reference to but a single preferred embodiment, it is obvious in the light of the above teachings that many modifications and variations are possible. Accordingly, the invention is not to be construed as limited by the illustrative example given hereinabove, since it is defined only by the scope of the appended claims.

What is claimed as new and desired to besecured by Letters Patent of the United States is:

1. A submersible ordnance detonating device for use in an aqueous surrounding medium comprising; a body member having therein a first chamber and a second chamber, bafiie means interconnecting said chambers, port means connecting the first chamber externally of the detonating device thereby to allow the surrounding medium to fill said first chamber, an electrically operated primer secured within said first chamber, a piston slideably arranged within said baffle means and in communication with said first chamber and adapted to be acted upon by a shock generated in said first chamber upon initiation of said primer, a firing pin integral with said piston and disposed within said second chamber, said firing pin being operable by initiation of said primer only when the medium filling said first chamber is a liquid, and a booster explosive in said second chamber adjacent to said firing pin for operation thereby.

2. An ordnance detonating device according to claim 1 further comprising; biasing spring means arranged within said bafiie means and urging said piston and said firing pin in a direction to prevent detonating contact of said firing pin with said booster explosive until the first chamber has been filled with a liquid and said primer has been initiated.

3. A detonating device for submersible ordnance comprising in combination; a body having a first chamber and a second chamber therein, an apertured b'afiie between said chambers, said bafile including a piston slidably disposed between said chambers and having a firing pin carried thereby, a booster charge disposed in the second chamber and adjacent to said firing pin for actuation thereby, a primer explosive disposed within the first chamber, said primer explosive and said piston being so spaced as to render shock waves caused by explosion of 'said primer explosive inefiective to operate said piston with sufiicient force to cause said firing pin portion thereof to actuate said booster charge when the first chamber is filled with air, and means for introducing a liquid into said first chamber to increase the shock transmission to said piston thereby to cause operation of said piston to detonate said booster upon initiation of said primer.

4. An underwater ordnance device for use in a water shock transmitting medium comprising; means forming a chamber having an open compartment in a wall thereof, a main explosive charge disposed within the device externally of the chamber and adjacent thereto, a booster charge disposed externally of the chamber and abutting said main charge, spring urged piston means slidably disposed in said compartment adjacent to said booster charge, an explosive primer disposed within Said chamber and adapted to forcibly drive said piston through a water shock transmitting medium into detonating contact with said booster charge, and vent means for filling the chamber with the water shock transmitting medium only when the ordnance device is submerged in a body of water. 

